Strain rate dependence of microstructural evolution in β titanium alloy during subtransus superplastic deformation

The aim of this study is to investigate the strain rate dependence of microstructural evolution in beta titanium alloy during subtransus superplastic deformation. Results show that the alpha phase plays a vital effect on beta titanium alloy during subtransus superplastic deformation, such as that the limiting of beta grain growth and the hindering of dislocations sliding. The higher strain rate resulting in elongating and cracking of alpha phase, while the lower strain rate leads to the growth of alpha phase. The beta phase was also elongated at the higher strain rate and the low strain rate is in favor of the spheroidizing. EBSD results show that the texture component moves from Phi = 90 degrees to Phi = 0 degrees along the alpha-fiber with the strain rates decrease from 2.78 x 10(-3) s(-1) to 2.78 x 10(-4)s(-1). (C) 2015 Elsevier B.V. All rights reserved.